Pump



Aug. 1954 A. E. GIROUX ETAL HIGH PRESSURE LOW PRESSURE RESERVOIR 2 Sheets-Sheet 1 FIG] INVENTORS ANTHONY E. GIROUX JACK R. HULME ATTORNEYS United States Patent 3,143,075 PUMP Anthony E. Giroux and Jack R. Hulme, Duncan, Okla, assignors to Halliburton Company, Duncan, Okla, a corporation of Delaware Filed lune 1'2, 1961, Ser. No. 116,521 3 Claims. (Cl. 103-37) This invention relates to a pump and, more particularly, to a high pressure pump which is capable of delivering a substantial volume of fluid at low and intermediate pressures.

The power requirements of a positive displacement pump are determined by the pressures which are to be developed and the size of the pump cylinder. The capacity of the pump is also determined by the size of the pump cylinder. Therefore, high pressure, large capacity pumps require large motors to power them and, consequently, they are uneconomical to operate. As a compromise, high pressure pumps usually have a small capacity.

If a small capacity pump is used to pump fluid into a large vessel, it will take a considerable amount of time for the pump to build up the desired pressure in the vessel. Attempts have been made to design compound pumps with a low pressure section to supply a large volume of fluid at low and intermediate pressures and a high pressure section to supply fluid at a high pressure. These attempts have been commercially unsuccessful, since the pumps have been complicated in design and diflicult or impractical to maintain.

Another disadvantage of the compound pumps heretofore proposed, is that they are inflexible in operation. Often, a low pressure pump and a high pressure pump will both be required at the same installation. Presently, it is necessary to use two pumps with ineflicient use of the pump motors and duplication of piping. It would be more eflicient to use a single pump motor to power a compound pump for the selective delivery of either low pressure fluid or high pressure fluid.

Accordingly, it is an object of this invention to provide a high pressure pump which is capable of delivering a substantial volume of fluid at low and intermediate pressures.

It is a further object of this invention to provide a compound pump which is simple in construction and economical in operation.

It is another object of this invention to provide a pump for delivering fluid selectively at a high pressure or allow pressure.

In accordance with a preferred embodiment of the invention, a double acting piston is mounted in a cylinder.

The power piston is operated, preferably, by air pressure. In accordance with conventional methods, high pressure air is admitted to one side of the piston and exhausted on the opposite side. At, or near the end of the stroke, the piston engages an actuator switch which operates a compound valve to close the exhaust valve and open the air valve to admit high pressure air to the opposite side of the piston and, reverse the direction of the movement of the piston. A similar actuator switch is mounted at the opposite end of the cylinder to automatically reverse the direction of movement of the piston.

A pump housing is secured to each end of the cylinder and connecting rods secured to opposite sides of the piston extend through compound cylinders in each of the housings. The larger cylinder which is closest to the piston, is the low pressure cylinder. The connecting rod has an enlarged portion which cooperates with the walls of the large cylinder to form a low pressure pump and the end of the connecting rod has a portion of reice duced diameter to cooperate with the walls of the smaller pump cylinder to form a high pressure pump. Intake and exhaust valves for each cylinder extend through the wall of the pump housing. The fluid exhaust for each cylinder is discharged through independent valves so that the pump cylinders may be connected in parallel or independently, as desired.

This preferred embodiment of the invention is illustrated in the accompanying drawings, in which:

FIGURE 1 is a side elevational view of the pump and a diagram of the associated piping;

FIGURE 2 is a quarter-sectional view of the power piston and pump housing through the low pressure intake valve and the high pressure exhaust valve; and

FIGURE 3 is a detail cross sectional view of the power cylinder and actuator switches.

The pump, as illustrated in FIGURE 1, is a double acting, compound pump and the arrangement of component parts in substantially identical on both sides of the power cylinder. Accordingly, only one side of the pump will be described in detail.

A fluid motor provides power for the pump and is mounted within a cylinder 1. Flanges 2, 2' enclose the ends of the cylinder 1. Pump housing 3, 3' are secured to the flanges 2, 2' by clamping rings 4, 4'. Referring to FIGURE 2, gaskets 5 on the housing 3 seal the joint between the housing 3 and the flange 2. Mounted within the cylinder 1 is a piston 6 which fits closely against the cylinder wall 1. A gasket 7 in the piston 6 reduces leakage of air past the piston. Secured to opposite sides of the piston 6 are connecting rods 8, 8'. Intermediate the ends of the connecting rod 8 is a low pressure plunger 9. The plunger 9 is clamped between a flange 10 on the connecting rod 8 and a lock washer 11 which is secured in a groove in the connecting rod. A spring 12 acting against the lock washer 11 and V-shaped packing 13 loads the packing to form a pressure tight seal for the plunger. The low pressure pump cylinder which cooperates with the plunger 9 has a removable sleeve 14 which is threadably secured in the pump housing 3 by means of threads 15. O-rings 16 on the exterior of the sleeve 14 prevent leakage of fluid around the sleeve.

Beyond the plunger 9, the connecting rod 8 has a portion of reduced diameter which forms the high pressure plunger 17. The high pressure cylinder 18 is formed in a plug 19 which is secured in the end of the housing 3 by means of threads 20. An O-ring 21 prevents leakage of fluid around the plug 19. A bore 22 communicates between the low pressure cylinder 14 and the high pressure cylinder 18. V-shaped packing 23 is compressed against a flange in the bore 22 by a coil spring 24 which is mounted in the bore between the plug 19 and packing 23 to form a tight seal between the high pressure cylinder and the low pressure cylinder.

The intake valves for the low pressure and high pressure cylinders are identical. As shown in FIGURE 2, which is a quarter sectional view of the pump through the low pressure intake valve and the high pressure exhaust valve, the intake valve is mounted in a hole which extends through the wall of the pump housing 3. The hole has a narrow passageway 25 which enters the low pressure cylinder 14 adjacent the bottom of the cylinder. An expanded portion 26 of the hole is provided with internal threads to engage corresponding threads on the valve body. The intake valve assembly comprises a base 27 which is threaded into the hole 26. A portion of the base 27 extends into the narrow passage 25 and is provided with O-rings 28 to prevent leakage of fluid around the base 27. At the junction between the narrow passageway 25 and the expanded, threaded portion 26 the hole is tapered to engage a corresponding tapered portion 29 of the base 27. The O-rings 28 and the tapered portion 29 form a dual seal to prevent the leakage of fluid around the valve base.

A valve body 30 is clamped to the base 27 by a nut 31. A central passageway 32 extends through the valve body 30 and a valve seat 33 is secured within an enlarged portion of the passageway 32. A ball 34 is mounted on the seat 33 and biased against displacement off the seat by a spring 35. A bore 36 in the valve base 27 communicates between the interior of the valve body 30 and the low pressure cylinder. A conduit 37 is threaded into the open end of the bore 32 to supply fluid from the reservoir.

Since all the exhaust valves are identical, the exhaust valve for the high pressure cylinder is shown in FIGURE 2 and will be described. The exhaust valve is mounted in a hole which extends through the pump housing 3 tocommunicate with the bore 22 at the open end of the cylinder 18. The ball valve assembly is identical to that shown and described in the intake valve assembly, except that the relative positions of the valve seat and the spring are reversed. In the exhaust valve, a valve seat 38 is mounted in the valve base 39 and a ball 40 is biased by a spring 41 against displacement by fluid flowing out of the plunger housing 3. The valve base 39 is clamped to the valve body 42 by a nut 43. A conduit 44 for pressurized fluid is secured to the valve assembly by a threaded collar 45.

As shown in FIGURE 1, the valves are mounted on the housing 3, 3' at approximately ninety degrees of rotation from each other. The intake and exhaust valves for each cylinder are in axial alignment on opposite sides of the pump housing 3, 3.

Referring to FIGURE 3, the piston 6 reciprocates in the cylinder 1. A plunger 46, 46 extends through a hole in the flange 2, 2'. The plunger 46, 46' is free to reciprocate in the hole, but is urged toward the piston 6 by a spring 47, 47' which is mounted on a bracket 48, 48'. Also mounted on the bracket 48, 48' is a switch 49, 49' with a rod 50, 50 which extends through the bracket to engage the end of the plunger 46, 46'. The switch 49, 49' is mechanically or electrically connected to the air supply valves for the air cylinder 1. As the piston 6 moves toward the right, as viewed in FIGURE 3, it engages the plunger 46 and, overcoming the forces of the spring 47 depresses the rod 50 to actuate the switch 49. The switch will shut off the supply of air and open the exhaust on the left side of the piston 6, and open the valve for the supply of air and close the exhaust on the right side of the piston. Increasing pressure on the right side of the piston 6 will cause it to move to the left. When the piston 6 reaches the plunger 46' it will depress the rod 50' to admit air to the left side of the piston.

One method of connecting the pump to provide a high volume flow of fluid at a high pressure is shown in FIG- URE l. The low pressure pumps are connected in parallel and the combined output flow from the low pressure pumps is fed through a check valve 51 to a main conduit 52. A low pressure bypass line is connected with a reservoir 53 through a bypass valve 54. Similarly, the high pressure pumps are connected in parallel and the output fed to the main conduit 52. A high pressure bypass is connected to the high pressure outlet to discharge to the reservoir 53 through a bypass valve 55. This piping arrangement permits fluid to be pumped by either the high pressure sections or by the low pressure sections of the pump, or by both at the same time.

In operation, referring to FIGURES 2 and 3, air under pressure is supplied to the cylinder 1 to drive the piston 6.

2, and enters the high pressure cylinder through an identical intake valve mounted on the pump housing 3. Dur ing the suction stroke, the plungers 9 and 17 will move to the left when viewed as in FIGURE 2, to draw the fluid into the cylinders 14 and 18. During the compression stroke, the plungers 9 and 17 will move to the right and the ball 34 of both intake valves will seat to prevent the flow of fluid back through the intake valves. As the pressure in the cylinders increases, the exhaust valves open to permit the fluid to flow out of the cylinders.

The high pressure plunger 17 is slightly smaller in diameter than the cylinder 18. During the suction stroke, the plunger 17 draws fluid through the intake valve, around the plunger 17 and into the cylinder 18. During the compression stroke, the plunger 17 moves to the right and compresses the fluid in the cylinder building up a pressure in the fluid in the cylinder 18. This pressure forces the fluid through the space between the wall of the cylinder 18 and the plunger 17 and out through the exhaust valve 42.

In normal operation, referring to FIGURE 1, both the high pressure and low pressure pumps are used at the same time to provide a maximum output volume until the pressure reaches a certain value. When the desired pressure is reached, the check valve 51 closes and the low pressure bypass valve 54 opens and fluid is pumped to the main 52 only by the high pressure section. The bypass valves 54 and 55 may be operated manually to stop flow of fluid through the main 52 while the pump is running.

To facilitate maintenance, all of the replaceable parts are readily accessible. The high pressure seals 21 and 23, for example, are subject to failure. Both of these seals may be replaced with a minimum of effort by removing the plug 19. The valves also may require servicing. This is accomplished by merely unscrewing the valve assembly from the housing and disassembling the valve by removing the nut 31. It is a simple matter to install and seal a valve assembly in the housing since the dual seals 28 and 29 automatically form a pressure tight seal between the valve assembly and the housing. As another feature, the low pressure cylinder 14 can be replaced if it becomes worn. Thus, the pump of this invention is an eflicient compound pump which is inexpensive to maintain. While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein, without departing from the invention as set forth in the claims.

We claim:

l. A fluid pump comprising a pump housing, said housing having a central bore extending therethrough, a plug removably secured in one end of the housing and axially aligned with the central bore, said bore forming a low pressure cylinder in the opposite end of the housing, said plug having a high pressure cylinder formed therein, said high pressure cylinder being axially aligned with said central bore, a connecting rod in the bore, means for reciprocating the connecting rod, a plunger on the connecting rod in position for cooperating with the low pressure cylinder to form a low pressure pump chamber, said rod extending into the high pressure cylinder and forming a high pressure plunger cooperating with the high pressure cylinder to form a high pressure pump chamber, said bore having a shoulder formed therein between said chambers, packing in said bore surrounding the connecting rod between the plug and the shoulder, spring means between said plug and said packing yieldably urging said packing against said shoulder whereby the flow of fluid between said chambers is prevented, high pressure valve means extending through the housing and in communication with said bore between the plug and the packing adjacent said spring, and low pressure valve means extending through the housing and in communication with said low pressure chamber.

2. A fluid pump comprising a pump housing, said housing having a central bore extending therethrough, a plug removably secured in one end of the housing and axially aligned with the central bore, said bore forming a low pressure cylinder in the opposite end of the housing, said plug having a high pressure cylinder formed therein, said high pressure cylinder being axially aligned with said central bore, a connecting rod in the bore, means for reciprocating the connecting rod, a plunger on the connecting rod in position for cooperating with the low pressure cylinder to form a low pressure pump chamber, said rod extending into the high pressure cylinder and forming a high pressure plunger cooperating with the high pressure cylinder to form a high pressure pump chamber, said bore having a shoulder formed therein between said chambers, packing in said bore surrounding the connecting rod between the plug and the shoulder, spring means between said plug and said packing yieldably urging said packing against said shoulder whereby the flow of fluid between said chambers is prevented, a low pressure inlet conduit and a low pressure outlet conduit, said conduits extending into the housing and communicating independently with said low pressure pump chamber, a high pressure inlet conduit and a high pressure outlet conduit, said high pressure conduits extending into the housing and communicating independently with said bore between the plug and the shoulder, and a one Way valve in each of said conduits preventing fluid from flowing toward said chambers through said outlet conduits and away from said chambers through said inlet conduits.

3. A fluid pump comprising a pump housing, said housing having a central bore extending therethrough, a plug removably secured in one end of the housing and axially aligned with the central bore, a sleeve removably secured in said bore forming a low pressure cylinder in the opposite end of the housing, said plug having a high pressure cylinder formed therein, said high pressure cylinder being axially aligned with said central bore, a connecting rod in the bore, means for reciprocating the connecting rod, a plunger on the connecting rod in position for cooperating with the low pressure cylinder to form a low pressure pump chamber, said rod extending into the high pressure cylinder and forming a high pressure plunger cooperating with the high pressure cylinder to form a high pressure pump chamber, said bore having a shoulder formed therein between said chambers, packing in said bore surrounding the connecting rod between the plug and the shoulder, spring means between said plug and said packing yieldably urging said packing against said shoulder whereby the flow of fluid between said chambers is prevented, a low pressure inlet conduit and a low pressure outlet conduit, said conduits extending into the housing and communicating independently with said low pressure pump chamber, between said sleeve and said packing, a high pressure inlet conduit and a high pressure outlet conduit, said high pressure conduits extending into the housing and communicating independently with said bore between the plug and the shoulder, and a one way valve in each of said conduits preventing fluid from flowing toward said chambers through said outlet conduits and away from said chambers through said inlet conduits.

References Cited in the file of this patent UNITED STATES PATENTS 355,669 Watkins Jan. 4, 1887 496,898 Reagan May 9, 1893 1,008,519 Barr Nov. 14, 1911 1,025,163 Schreidt May 7, 1912 1,032,352 House July 9, 1912 1,552,696 Hartsock Sept, 8, 1925 1,820,236 Loud Aug. 25, 1931 2,349,150 Falasconi May 16, 1944 2,365,234 Wineman Dec. 19, 1944 2,366,388 Crosby Ian. 2, 1945 2,486,495 Rider Nov. 1, 1949 2,532,856 Ray Dec. 5, 1950 2,751,889 Mohler June 26, 1956 2,755,739 Euwe July 24, 1956 2,808,003 Staege Oct. 1, 1957 2,820,415 Born Jan. 21, 1958 2,826,149 Wrigley Mar. 11, 1958 2,856,116 Hogan Oct. 14, 1958 2,861,519 Houle Nov. 25, 1958 2,896,663 Mena July 28, 1959 2,938,465 McFarland et a1 May 31, 1960 2,989,001 Wilkenloh et al. June 20, 1961 3,070,023 Glasgow Dec. 25, 1962 FOREIGN PATENTS 50,524 Austria of 1910 175,655 Austria Aug. 10, 1953 844,536 Germany July 21, 1952 1,090,111 France Oct. 1, 1951 

1. A FLUID PUMP COMPRISING A PUMP HOUSING, SAID HOUSING HAVING A CENTRAL BORE EXTENDING THERETHROUGH, A PLUG REMOVABLY SECURED IN ONE END OF THE HOUSING AND AXIALLY ALIGNED WITH THE CENTRAL BORE, SAID BORE FORMING A LOW PRESSURE CYLINDER IN THE OPPOSITE END OF THE HOUSING, SAID PLUG HAVING A HIGH PRESSURE CYLINDER FORMED THEREIN, SAID HIGH PRESSURE CYLINDER BEING AXIALLY ALIGNED WITH SAID CENTRAL BORE, A CONNECTING ROD IN THE BORE, MEANS FOR RECIPROCATING THE CONNECTING ROD, A PLUNGER ON THE CONNECTING ROD IN POSITION FOR COOPERATING WITH THE LOW PRESSURE CYLINDER TO FORM A LOW PRESSURE PUMP CHAMBER, SAID ROD EXTENDING INTO THE HIGH PRESSURE CYLINDER AND FORMING A HIGH PRESSURE PLUNGER COOPERATING WITH THE HIGH PRESSURE CYLINDER TO FORM A HIGH PRESSURE PUMP CHAMBER, SAID BORE HAVING A SHOULDER FORMED THEREIN BETWEEN SAID CHAMBERS, PACKING IN SAID BORE SURROUNDING THE CONNECTING ROD BETWEEN THE PLUG AND THE SHOULDER, SPRING MEANS BETWEEN SAID PLUG AND SAID PACKING YIELDABLY URGING SAID PACKING AGAINST SAID SHOULDER WHEREBY THE FLOW OF FLUID BETWEEN SAID CHAMBERS IS PREVENTED, HIGH PRESSURE VALVE MEANS EXTENDING THROUGH THE HOUSING AND IN COMMUNICATION WITH SAID BORE BETWEEN THE PLUG AND THE PACKING ADJACENT SAID SPRING, AND LOW PRESSURE VALVE MEANS EXTENDING THROUGH THE HOUSING AND IN COMMUNICATION WITH SAID LOW PRESSURE CHAMBER. 